US6346089B1 - Endoprosthesis for the treatment of blood-vessel bifurcation stenosis and purpose-built installation device - Google Patents

Abstract

An endoprosthesis for the treatment of blood vessel bifurcation stenosis. The endoprosthesis comprises three tubular sections and two connections. A distal section is aligned at least approximately with a proximal section. The first distal section is intended for insertion into a first blood vessel branching off on the bifurcation. The first distal section is linked to the proximal section by a first lateral connector. A second distal section, located at the side of the first distal section, is intended for insertion into a second vessel branching off from bifurcation. The two distal sections have their proximal ends linked by a second connector.

Description

This is a divisional application of Ser. No. 08/945,973 filed Jan. 26,1998, now U.S. Pat. No. 6,183,509.

This invention relates to the field of endoprostheses for the treatment of blood-vessel bifurcation stenosis.

This invention also relates to a purpose-built installation device.

BACKGROUND

It has already been suggested that stenosis found in coronary arteries be treated using endoprostheses formed from tubular structures perforated With a grid pattern of slits and consequently expandable following placement at the site of stenosis. In most cases these endoprostheses are expanded by inflating a balloon which is placed inside them and subsequently withdrawn.

Generally speaking, endoprostheses of this type may be said to have already given good service.

They are not, however, fully satisfactory.

The applicant has, in particular, observed that standard endoprostheses are not fully satisfactory when, as is frequently the case, there is stenosis at a blood-vessel bifurcation. In such cases, treatment using standard endoprostheses requires two separate endoprostheses. One of these is placed in each of the two vessels branching off from the bifurcation and their positioning in relation to each other is adjusted as finely as possible to ensure optimal cover of the bifurcation area.

A primary goal of this invention is to develop existing endoprostheses in order to facilitate and improve treatment of blood-vessel bifurcation stenosis.

This goal is attained by this invention through the use of an endoprosthesis comprising three tubular sections and two connectors, namely:

a proximal section;

a first distal section aligned at least approximately with the proximal section and intended for insertion into one of the vessels branching off from the bifurcation, this distal section being attached to the proximal section by means of a laterally positioned connector; and

a second distal section placed at the side of the first distal section and intended for insertion into the second vessel branching off from the bifurcation, the two distal sections having their proximal ends joined by the second connector.

In accordance with another advantageous feature of this invention, the distal end of the proximal section is chamfered and the proximal end of the second distal section is tapered at the other side of the second connector and fits into the chamfer in the proximal section.

The above-mentioned chamfered shapes and tapered ends may have a variety of embodiments. They may, in particular, be delimited by flat or curved surfaces.

Another important goal of this invention is to perfect the method of installing the above-mentioned endoprostheses.

According to this invention this goal is attained by using a double-balloon system, as follows:

a first balloon of suitable length for insertion into two approximately aligned sections of the blood vessel to be treated: the main stem and the first branching blood vessel, on either side of the bifurcation area respectively; and

a second balloon of suitable nature for insertion into the second blood vessel branching off from the bifurcation.

In accordance with another advantageous feature of the invention, the first balloon incorporates a lateral recess to be positioned facing the bifurcation area with a view to housing the proximal end of the second balloon.

In accordance with another advantageous feature of this invention, the distal portion of the first balloon located downstream of the recess is of smaller diameter than the proximal portion of the balloon located upstream of the recess.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features, goals and advantages of the invention will be apparent on reading the following detailed description as illustrated in the corresponding accompanying drawings, which are given as non-exhaustive examples and in which:

FIG. 1 is a schematic side view of an endoprosthesis in accordance with this invention;

FIG. 2 is a perspective view of the same endoprosthesis;

FIG. 3 is another perspective view of the same endoprosthesis after relative inclination of the distal sections;

FIG. 4 is a view of the same endoprosthesis following expansion of the various tubular sections from which it is formed;

FIG. 5 is a schematic illustration of an endoprosthesis combined with the device for installing it, prior to implantation in a stenosis-affected bifurcation area;

FIG. 6 is a view of the same instrument following implantation in a bifurcation and expansion of the proximal section and one distal section;

FIG. 7 is a view of the same endoprosthesis after expansion of the three sections from which it is formed;

FIG. 8 is a schematic side view of the first balloon in accordance with the invention;

FIG. 9 is a side view of the second balloon in accordance with the invention;

FIG. 10 is an overall view of an installation instrument comprising two balloons working together in accordance with the invention;

FIG. 11 is another side view of the balloon-based installation system in accordance with the invention;

FIG. 12 is an overall view of the same balloon-based installation tool combined with means of inflation; and

FIG. 13 is a schematic cross-sectional view of a feeder tube for the double-balloon system.

DETAILED DESCRIPTION

The first item described will be the structure ofendoprosthesis100 in accordance with the invention and illustrated in FIGS. 1 to7. As was mentioned earlier,endoprosthesis100 comprises three tubular sections (110,120 and140) and two connectors (130 and150).

The first section (110) is a proximal section having as itscentre axis111. It is intended for insertion into main stem T1 of blood vessel V for treatment, upstream of the bifurcation.

The first distal section (120) having as itssection axis121 is at least approximately aligned withproximal section110 prior to use. This firstdistal section120 is intended for insertion into blood vessel T2 branching off from the bifurcation as is seen in particular in FIGS. 6 and 7.

The first distal section (120) is attached toproximal section110 by the first lateral connector (130).

The second distal section (140), having as itsaxis141, is positioned at the side of the first distal section (120), and has the advantage of being parallel to the latter, prior to use. The second distal section (140) is intended to be inserted into blood vessel T3 branching off from the bifurcation, as is seen in particular in FIGS. 6 and 7.

The twodistal sections120 and140 have their proximal ends (122 and142) linked by the second connector (150).

Each ofsection110,120 and140 is preferably formed from a tubular component perforated with a grid pattern of slits such that the structure ofsections110,120 and140 allows them to expand along their circumferences.

In practice,section110,120 and140 ofendoprosthesis100 can be manufactured from extruded cylindrical parts made of a bendable metal alloy such as 316L stainless steel. The external diameter of section of110,120 and140 typically ranges from 1 to 1.2 mm prior to use:

There can be a range of variants of the grid pattern cut intosections110,120 and140. The opening may take the form of a hexagon or diamond, as shown in the accompanying figures, taking on the appearance of grating following, expansion against the inner surface of the coronary artery by means of a cylindrical balloon placed inside.

As the basic structure of expandabletubular components110,120 and140 and the material from which they are made are familiar to those skilled in the art, these particulars will not be described in detail in what follows.

The threesections110,120 and140 are preferably of equal diameter prior to expansion, i.e. prior to use.

The respective axes (111,121 and141) ofsections110,120 and140 are coplanar and determine a plane of symmetry for the endoprosthesis. This plane of symmetry is parallel to the plane of FIG.1.

The first connector (130) has as its centre the above-mentioned plane of symmetry determined byaxes111,121 and141.

Connector130 links an area ofdistal end113 ofproximal section110 with an area ofproximal end122 of the first distal section (120). Yet more specifically,articulation130 preferably consists of a strip of constant width parallel toaxes111 and121.Articulation130 is diametrically opposite the second distal section (140) with respect toaxes111 and121.

Distal end113 ofproximal section110 is provided withchamfer115 in its peripheral area situatedopposite connector130.Chamfer115 can be determined by a plane that is inclined with respect toaxis111, perpendicular to the above-mentioned plane of symmetry or, again, be curved, for instance, concave with respect todistal section120. Angular opening of the wall ofproximal section110 thus increases starting fromconnector130 and turns through 360,°i.e. a complete tubular form aroundaxis111.

This cant (115) forms a type of arch located on the side oppositeconnector130 embodying in the cylindrical structure formingproximal section110 the shape of the ostium of the blood vessel branching off from the coronary bifurcation onto which it will be applied.

Furthermore,proximal end142 of the second distal section (140) is tapered at the other side of the second connector (150). It stretches forwards in its peripheral area opposite the second connector (150). This tapered portion (144) may also be determined by a plane that is inclined with reference toaxis121, perpendicular to the plane of symmetry or, again, by a curved surface.

After expansion, as is illustrated in FIG. 4 for example, when the endoprosthesis is installed at the bifurcation of the two coronary arteries,distal portion113 with the corner cut off (115) ofproximal section110 is fixed together harmoniously with the proximal (114) ofsection140 of the endoprosthesis and ensures maximum coverage of the dilated coronary bifurcation area.

In this way, once in place, the whole of the grid of the bifurcated endoprosthesis (100) covers the proximal and distal portions of the two coronary branching arteries and the whole of the dilated bifurcation area.

The first connector (130) preferably forms an integral part, i.e. it is not joined ontosections110 and120.

In other words, the first connector (130) andsections110 and120 are preferably manufactured from a single part in whichconnector130 is formed via machining.

The second connector (150) is also centred with reference to the plane of symmetry determined byaxes111,121 and141.

However, whereas the first connector (130) extends in a direction that is parallel toaxes111 and121, the second connector (150) extends in a direction that is transversal to the above-mentionedaxes111,121 and141 and links adjacent areas of proximal ends122 and142 ofdistal sections120 and140.

The second connector (150) is preferably joined toproximal ends122 and142 orsections120 and140 by means of, for example, laser welding.

This aspect of the invention can, naturally, be embodied by a range of variants in that the second connector (150) could form an integral part withdistal sections120 and140 formed from a single part whileconnector130 would be joined by means of, for example, laser welding to the distal end ofproximal section110 and the proximal end ofdistal section120.

In accordance with a particular embodiment, given as a non-exhaustive example,bifurcated endoprosthesis100 for the coronary artery conforming with this invention has the following dimensions:

the total length ofendoprosthesis100 measured fromproximal end112 ofproximal section110 todistal end123 ofdistal section120 is of the order of 15 mm;

the diameter ofsections110,120 and140 is of the order of 1 mm prior to expansion;

the length ofproximal section110 is of the order of 7.5 mm prior to expansion;

the length ofdistal section120 is of the order of 7 mm prior to expansion;

the length ofdistal section140 is of the order of 9 mm prior to expansion;

the length ofconnector130 is of the order of 0.5 to 1 mm; and

the diameter ofdistal sections120 and140 in their expanded state is of the order of 3 mm while the diameter ofproximal section110 is of the order of 3.5 mm.

A description now follows of the structure of the instrument fitted with a double asymmetric balloon conforming with this invention which is shown in FIG. 8 et seqq.

Essentially, this instrument (200) comprises two balloons (210 and230). The first balloon (210) is of a length consonant with its purpose of being positioned inside two approximately aligned sections (T1 and T2) of vessel V for treatment: main stem T1 and a branching vessel T2, situated one on either side of the bifurcation area respectively, or, again, of being positioned insideproximal section110 anddistal section120 ofendoprosthesis100.

As regards the second balloon (230), this is consonant with its purpose of being positioned in the second blood vessel (T3) branching off from the bifurcation.Balloon230 is preferably shorter thanballoon210. As shown in the accompanying figures, the twoballoons210 and230 are preferably formed from generally cylindrical elongated tubular items centred uponaxes212 and232 and having their ends (214 and216;234 and236) more or less rounded.

The main balloon (210) preferably incorporates a recess in its side (218) suitable for housingproximal end236 of the second balloon (230) as shown in FIG.10.

Furthermore,proximal portion219 ofballoon210 located upstream ofrecess218 is preferably of greater diameter thandistal portion217 of the same balloon located downstream ofrecess218.

Each of theballoons210 and230 is preferably fitted With a radio-opaque tracer (220 and240).Tracers220 and240 are preferably located at the centres of theirrespective balloons210 and230.Tracers220 and240 may, for example, be carried by hollowinternal tubes221 and241 housingmetallic guides222 and242 having as theircentres axes212 and232 and passing axially throughballoons210 and230 respectively.Tracers220 and240 are preferably located halfway alongballoons210 and230.

Balloons210 and230 are prolonged at their proximal ends216 and236 by, respectively,tubes224 and244, of narrow cross-section, designed to feed and, consequently, dilateballoons210 and230.

Tubes224 and244 preferably house guides222 and242. More specifically, each of the twotubes224 and244 preferably has two lumina: the first lumen houses a guide (222 and242) and opens into the associated internal tube (221 and241) and the second lumen, used for inflating the balloons, opens into the inside surface of the balloons (210 and230).

The above-mentionedinternal tubes221 and241 and first lumina are not connected with the internal surface ofballoons210 and230.

Furthermore,internal tube221 inside the first balloon (210) is preferably off-centre with respect toaxis212 in order to allow for the presence ofrecess218 as is seen in FIG.8.

Inflation tubes224 and244 are joined at a certain distance fromballoons210 and230 and are preferably attached by their proximal ends to a stiffer but both flexible and hollowcommon component250 with two internal lumina (253 and254) linked withinflation tubes224 and244 respectively or, more specifically, the said above-mentioned second inflation lumina of these tubes.Component250 is, moreover, itself fitted at its proximal end (252) with two connection systems with fluid sources linked withlumina253 and254 respectively, allowingballoons210 and230 to be expanded. These connection systems may, for example, be of the type known as “Luer-Lock”. A variant on this is that the above-mentioned connection systems may be adapted to take a standard inflation syringe tip.

It is important that the above-mentioned connection systems communicating with, respectively,lumina253 and254 formed insidecomponent250 should allow the two balloons (210 and230) to be expanded separately.

Balloons210 and230 are preferably covered prior to use with a removable sheath (260).Sheath260 covers the full length ofendoprosthesis100, i.e. preferably a minimum of 15 to 20 mm.Sheath260 is preferably linked at its proximal end to a wire (262) facilitating removal ofsheath260 by pulling the saidwire262.Wire262 preferably passes throughcommon tube250.

Sheath260 can, however, be omitted when the balloon system alone is used, i.e. withoutendoprosthesis100.

The “Luer-Lock” connection systems shown in FIG. 12 are referred to as252. Furthermore, reference n°270 in FIG. 12 labels a schematic inflation system comprising a pressure gauge (272) adapted for linkage to one of the connection system (252) with a view to dilating one ofballoons210 and230.

Reference n°253 and n°254 in FIG. 13 label the two feeder lumina linkingconnection systems252 withtubes224 and244 respectively. In addition, reference n°255 in FIG. 13 labels the lumen housing the wire (262) facilitating the removal ofsheath260.

In accordance with a particular embodiment that is, naturally, non-exhaustive, asymmetricdouble balloon200 for coronary angioplasty conforming with this invention has the following dimensions:

guide-wires222 and242 are 0.036 cm (0.014 inch) guide-wires;

the longer balloon (210) is 20 to 25 mm in length, depending on the model;

its proximal portion (219) is approximately 3.5 mm in diameter and approximately 6.5 mmn in length after inflation;

recess218 is approximately 3.5 mm in length;

distal portion217 is approximately 10 mm in length and approximately 3 mm in diameter after inflation;

the second balloon (230) is approximately 13 mm in length and approximately 3 mm in diameter after inflation;

tubes224 and244 are joined approximately 10 mm from the proximal end (216) ofballoon210;

the lengths of the twotubes224 and244 between the point at which they join andcommon component250 may range from approximately 20 to 30 cm;

the overall length, includingballoons210 and230 and their feeder tubes is preferably approximately 135 mm;

the length ofcommon tube250 ranges from approximately 110 to 115 mm; and

the outer diameter of the device withballoons210 and230 completely deflated preferably does not exceed 2 mm, so that the whole unit including the twoballoons210 and230 andfeeder tubes224 and244 may pass through an8F guiding-catheter with an internal diameter of 2.6 mm. The case is the same in the version of the balloon device fitted withendoprosthesis100 andsheath260.

The portion oftubes224 and244 that is located downstream of guide-wire exits223 and243, is preferably made of plastic.

The portion oftubes224 and244, includingcommon portion250, that is located upstream ofexits223 and243 may be made of plastic or metal.

This tube (224,244 and250) must be as hydrophilic as possible in order to be able to slide inside its carrier catheter or guiding catheter.

It should be noted thatballoons210 and230 are mutually independent. They are indirectly linked only in the area ofcommon tube250.

Guide-wires222 and242 preferably emerge fromtubes224 and244 on the nearer side ofcommon section250, as is seen in FIG.11. Exit points223 and243 of guide-wires222 and242 are preferably at a slight distance from each other and are marked differently for identification.

A description now follows of the process for installingendoprosthesis100 using asymmetricdouble balloon200 in accordance with this invention.

Prior to use, the unit combining the two balloons (210 and230) andbifurcated endoprosthesis100 is protected by coveringsheath260. This unit fitted withsheath260 is firstly maneuvered close to the bifurcation stenosis area. Its position is monitored using radio-opaque tracers220 and240.

Once the balloon (210 and230)/endoprosthesis (100) unit has arrived at the bifurcation, above-mentionedsheath260 can be withdrawn by pullingwire262.

Afterprotective sheath260 has been withdrawn, guide-wires222 and242, which have been inserted into blood vessels T2 and T3 branching off from the coronary bifurcation, are manipulated.Balloons210 and230, located respectively insideproximal section110 anddistal section120 in the case ofballoon210 and insidedistal section140 in the case ofballoon230, are still in a deflated state at this stage. Once it has been ascertained thatsections120 and140 of the endoprosthesis have been correctly positioned at the bifurcation using radio-opaque tracers220 and240 contained in the balloons, the balloons can be inflated.

To this end, the first asymmetric balloon (210), i.e. the longer balloon which facilitates expansion of the main structure (110) of the endoprosthesis and ofsection120, aligned with it, is preferably inflated first. Typicallyballoon210 thus increasesproximal portion110 of the endoprosthesis to 3.5 mm anddistal portion120 to 3 mm.

This is followed by inflation of the shorter balloon (230), whoseproximal end236 fillsrecess218 inballoon210. Inflatingballoon230 thus dilatessection140 of the endoprosthesis. The proximal tapered shape ofsection140 fits into the truncated form or form with its corner missing (115) of the main or proximal structure (110) of the endoprosthesis opposite and thus completely covers the ostial portion or bifurcation area of the coronary branching artery dilated and stented in the course of this procedure.

Once the bifurcated endoprosthesis has been deployed and installed, as shown in FIG.7.balloons210 and230 can be deflated and withdrawn.

Balloons210 and230 can be deflated and withdrawn simultaneously or separately. as appropriate, after being detached from the unit.

It is advantageous forballoons210 and230 to be made from an elastic material manufactured from a plastic polymer.

This invention is not, of course, restricted to the particular embodiment described above but stems to any and all variants consistent with the idea embodied.

In particular, the invention is not limited to dilation of a bifurcation area in a coronary artery showing a lesion at thebifurcation using endoprosthesis100 and employing dilation ofballoons210 and230. The invention may also apply to other blood-vessel bifurcations, arteries or veins, such as, for example and non-limitatively, renal arteries, supra-aortic trunci, arteries leading from the aorta to the abdomen or to the low limbs, etc.

A particular variant of the invention is one in whichballoon210 may incorporate two portions (217 and219), distal and proximal respectively, located on either side ofrecess218 and having the same diameter.

During deployment,balloon230 may be inflated beforeballoon210.

Furthermore, installation and dilation ofbifurcated endoprosthesis100 may be envisaged using systems other than the double balloon structure illustrated in FIG. 8 et seqq., and, in a corollary manner, the double-balloon system (200) may be used as a double balloon for coronary bifurcation lesion angioplasty not involving use of an endoprosthesis.

According to a variant of the invention, thefirst balloon210 is symetric about itslongitudinal axis212. In other words therecess218 is annular and symetric of revolution about thisaxis212.

Claims (30)

What is claimed is:

1. A balloon system for dilating blood vessels comprising:

a first balloon (210) of suitable length for being positioned in two approximately aligned sections (T1 and T2) for the vessel for treatment: a main stem (T1) and a branching vessel (V2), located one on each side of a bifurcation area; and

a second balloon (230) suitable for positioning in a second blood vessel (T3) branching off from the bifurcation wherein the first balloon (210) incorporates a lateral recess (218) intended for positioning opposite the bifurcation area in order to house the proximal end (236) of the second balloon (320).

2. A system, as claimed inclaim 1, characterised by the fact that the proximal portion (219) of the first balloon (210) located upstream of the recess (218) is of greater diameter than the distal portion (217) of the same balloon located downstream of the recess.

3. A system, as claimed inclaim 1, characterised by the fact that each balloon has a radio-opaque tracer (220 and240).

4. A system, as claimed inclaim 1, characterised by the fact that the two balloons (210 and230) are placed in a removable sheath (260) combined with a manoeuvring wire (262).

5. A system, as claimed in one ofclaim 1, characterised by the fact that each balloon (210 and230) has an inflation tube (224 and244) protruding from its proximal end.

6. A system, as claimed inclaim 1, characterised by the fact that the two inflation tubes (224 and244) are joined to a common component (250) comprising two lumina at a certain distance from the proximal end of the balloons (210 and230).

7. A system, as claimed inclaim 1, characterised by the fact that each balloon (210 and230) is combined with a guide (121 and141).

8. A system, as claimed inclaim 1, characterised by the fact that the second balloon (230) is shorter than the first balloon (210).

9. The use of the system defined byclaim 1 for dilation of an endoprosthesis for the treatment of blood-vessel bifurcation stenosis at a level of a bifurcation area between a main vessel stem and two secondary vessel stems having a diameter inferior to a diameter of the main vessel stem and branching off from the main vessel stem at the bifurcation comprising three tubular sections (110,120 and140) and two articulation connectors (130 and150):

a proximal section (110) intended for insertion into the main vessel stem;

a first distal section (120) aligned at least approximately with the proximal section (110) and intended for insertion into a first secondary blood vessel (T2) branching off from the bifurcation, the first distal section (120) being linked to the proximal section (110) by a lateral connector (130); and

a second distal section (140) located at the side of the first distal section (120) and intended for insertion into a second secondary blood vessel (T3) branching off from the bifurcation, both distal sections (120 and140) having their proximal ends linked by a second connector (150) which allows relative pivoting of said distal sections (120 and140) about said second connector (150) to accommodate the blood-vessel bifurcation.

10. The use of the system consistent withclaim 1 for bifurcation lesion angioplasty.

11. A balloon system for dilating blood vessels comprising:

a first balloon (210) of suitable length for being positioned in two approximately aligned sections (T1 and T2) for the vessel for treatment:

a main stem (T1) and a branching vessel (V2), located one on each side of a bifurcation area;

a second balloon (230) suitable for positioning in a second blood vessel (T3) branching off from the bifurcation wherein a proximal portion (219) of the first balloon (210) located upstream of a recess (218) is of greater diameter than a distal portion (217) of the same balloon located downstream of the recess.

12. A system, as claimed inclaim 11, wherein the first balloon (210) incorporates a lateral recess (218) intended for positioning opposite the bifurcation area in order to house a proximal end (236) of the second balloon (320).

13. A system, as claimed inclaim 11, wherein each balloon has a radio-opaque tracer (220 and240).

14. A system, as claimed inclaim 11, wherein the two balloons (210) and230) are placed in a removable sheet (260) combined with a maneuvering wire (262).

15. A system, as claimed in one ofclaims 11 to14, wherein each balloon (210 and230) has an inflation tube (224 and244) protruding from its proximal end.

16. A system, as claimed inclaim 11, wherein the two inflation tubes (224 and244) are joined to a common component (250) comprising two lumina at a certain distance form the proximal end of the balloons (210 and230).

17. A system, as claimed inclaim 11, wherein each balloon (210 and230) is combined with a guide (121 and141).

18. A system, as claimed inclaim 11, wherein the second balloon (230) is shorter than the first balloon (210).

19. The use of the system defined byclaim 11 for dilation of an endoprosthesis for the treatment of blood-vessel bifurcation stenosis at a level of a bifurcation area between a main vessel stem and two secondary vessel stems having a diameter inferior to a diameter of the main vessel stem and branching off from the main vessel stem at the bifurcation comprising three tubular sections (110,120 and140) and two articulation connectors (130 and150):

a proximal section (110) intended for insertion into the main vessel stem;

a first distal section (120) aligned at least approximately with the proximal section (110) and intended for insertion into a first secondary blood vessel (T2) branching off from the bifurcation, the first distal section (120) being linked to the proximal section (110) by a lateral connector (130); and

a second distal section (140) located at the side of the first distal section (120) and intended for insertion into a second secondary blood vessel (T3) branching off from the bifurcation, both distal sections (120 and140) having their proximal ends linked by a second connector (150) which allows relative pivoting of said distal sections (120 and140) about said second connector (150) to accommodate the blood-vessel bifurcation.

20. The use of the system defined byclaim 11 for bifurcation lesion angioplasty.

21. A balloon system for dilating blood vessels comprising:

a first balloon (210) of suitable length for being positioned in two approximately aligned sections (T1 and T2) for the vessel for treatment: a main stem (T1) and a branching vessel (V2), located one on each side of a bifurcation area; and

a second balloon (230) suitable for positioning in a second blood vessel (T3) branching off from the bifurcation wherein the second balloon (230) is shorter than the first balloon (210).

22. A system, as claimed inclaim 21, wherein the first balloon (210) incorporates a lateral recess (218) intended for positioning opposite the bifurcation area in order to house a proximal end (236) of the second balloon (320).

23. A system, as claimed inclaim 21, wherein a proximal portion (219) of the first balloon (210) located upstream of a recess (218) is of greater diameter than a distal portion (217) of the same balloon located downstream of the recess.

24. A system, as claimed inclaim 21, wherein each balloon has a radio-opaque tracer (220 and240).

25. A system, as claimed inclaim 21, wherein the two balloons (210) and230) are placed in a removable sheet (260) combined with a maneuvering wire (262).

26. A system, as claimed in one ofclaims 21 to25, characterized by the fact that each balloon (210 and230) has an inflation tube (224 and244) protruding from its proximal end.

27. A system, as claimed inclaim 21, wherein the two inflation tubes (224 and244) are joined to a common component (250) comprising two lumina at a certain distance form the proximal end of the balloons (210 and230).

28. A system, as claimed inclaim 21, wherein each balloon (210 and230) is combined with a guide (121 and141).

29. The use of the system defined byclaim 21 for dilation of an endoprosthesis for the treatment of blood-vessel bifurcation stenosis at a level of a bifurcation area between a main vessel stem and two secondary vessel stems having a diameter inferior to a diameter of the main vessel stem and branching off from the main vessel stem at the bifurcation comprising three tubular sections (110,120 and140) and two articulation connectors (130 and150):

a proximal section (110) intended for insertion into the main vessel stem;

a first distal section (120) aligned at least approximately with the proximal section (110) and intended for insertion into a first secondary blood vessel (T2) branching off from the bifurcation, the first distal section (120) being linked to the proximal section (110) by a lateral connector (130); and

a second distal section (140) located at the side of the first distal section (120) and intended for insertion into a second secondary blood vessel (T3) branching off from the bifurcation, both distal sections (120 and140) having their proximal ends linked by a second connector (150) which allows relative pivoting of said distal sections (120 and140) about said second connector (150) to accommodate the blood-vessel bifurcation.

30. The use of the system defined byclaim 21 for bifurcation lesion angioplasty.

Images